Sect VIII div 2- new revisions ?

[davefitz]

I have heard that there is to be a rewrite and complete revision to ASME Sect VIII div 2, and that the changes were summarized in the recent PVP conference.

Can anyone familiar with these chagnes post a summary here?

 

[jte]

Davefitz-

I was at the PVP and heard Mr. Osage of Equity Engineering present his paper and have a copy of the printed edition. Equity Engineering has been contracted to provide substantial support for the rewrite, and Mr. Osage has been around for a while (see also API-579), so he knows what he's talking about. A quick overview of his paper, "An Overview of the New ASME Section VIII, Division 2 Pressure Vessel Code" published in PVP Vol. 453, Pressure Vessel and Piping Codes and Standards - 2003:

Organized into nine parts. Eliminate mandatory and non-mandatory appendices - now they will be annexes (no, I don't know the difference).

Lots of changes to materials: New design stress basis (UTS/2.4 or 2/3 yield), new format for allowable stresses (they'll lump a bunch of materials together, similar to the way yield stresses are presented currently), new toughness rules, new compressive stress curves (no more A and B factors).

Design by rule: Approach similar to API-579, code cases 2286 (comp. stress) and 2261 (SE and torispherical heads) used, new nozzle rules for pressure and external loads, etc. etc.

Design by analysis: Minimum wall thickness can be established using Design-By-Analysis, Design-By-Rule requirements do not need to be satisfied. (There is a misconception out there now that the current Div. 2 allows this. It does not, so this is a big change.) Accomodate FEA better, new procedures for limit load design and fatigue.

Changes to fabrication tolerances and PWHT requirements (can be set based on the amount of desired stress reduction).

A weld joint efficiency of 1 can be achieved for spot inspection in certain cases. UT accepted in lieu of RT.

Inclusion of Code Case 2211 philosophy (overpressure protection through system design).

An overview of an overview. The paper's pretty concise, just over two pages, it's hard to not just retype the whole thing - but if you want it that bad, support the industry and buy a copy of the entire volume for $55 from

http://members.asme.org/catalog/Cat...umberOfItems=100&SubCategory=PVP&StartRow=101

jt

 

[davefitz]

Thanks for the update.